Sufism is a mystic tradition within Islam which encompasses a diverse range of beliefs and practices dedicated to divine love and the cultivation of the heart.

Sufism has been defined as a type of knowledge by the great Sufi masters. Shaykh Ahmad Zarruq, a 15th century Sufi who wrote The Principles of Sufism, defined Sufism as "a science whose objective is the reparation of the heart and turning it away from all else but God." Ibn 'Ajiba, one of the best known Sufi masters defined Sufism as "a science through which one can know how to travel into the presence of the Divine, purify one’s inward from filth and beautify it with a variety of praiseworthy traits."

The Tariqas, or Sufi orders, are associated with Sunni Islam. It has been suggested that Sufi thought emerged from the Middle East in the eighth century, but adherents are now found around the world.

The conventional view is that the word originates from Suf (صوف), the Arabic word for wool, referring to the simple cloaks the early Muslim ascetics wore. However, not all sufis wear cloaks or clothes of wool. Another etymological theory states that the root word of Sufi is the Arabic word safa (صفا), meaning purity. This places the emphasis of Sufism on purity of heart and soul.

Others suggest the origin is from "Ashab al-Suffa" ("Companions of the Veranda") or "Ahl al-Suffa" ("People of the Veranda"), who were a group of Muslims during the time of the Prophet Mohammad(S.A.W) who spent much of their time on the veranda of the Prophet's mosque devoted to prayer. Yet another etymology, advanced by the 10th century author Al-Biruni is that the word, as 'Sufiya', is linked with the Greek term for 'Wisdom' - 'Sophia', although for various reasons this derivation is not accepted by many at the present.

The essence of Being/Truths/God is devoid of every form and quality, and hence unmanifested, yet it is inseparable from every form and phenomenon either material or spiritual. It is often understood to imply that every phenomenon is an aspect of Truth and at the same time attribution of existence to it is false. The chief aim of all Sufis then is to let go of all notions of duality, including a conception of an individual self, and to realize the divine unity.

Sufis teach in personal groups, as the counsel of the master is considered necessary for the growth of the pupil. They make extensive use of parable, allegory, and metaphor, and it is held by Sufis that meaning can only be reached through a process of seeking the truth, and knowledge of oneself. Although philosophies vary among different Sufi orders, Sufism as a whole is primarily concerned with direct personal experience, and as such may be compared to various forms of mysticism such as Hesychasm, Zen Buddhism, Gnosticism and Christian mysticism.

A significant part of Persian literature comes from the Sufis, who created books of poetry containing the teachings of the Sufis. Some of the more notable examples of this poetry are the Walled Garden of Truth, Rubaiyat of Omar Khayyam, the Conference of the Birds and the Masnavi.

Sufism is generally believed to have originated among Muslims near Basra in modern Iraq. Almost all traditional Sufi schools (or "orders") trace their "chains of transmission" back to the Prophet via his cousin and son-in-law Imam Ali ibn Abi Talib; the Naqshbandi order is a notable exception to this rule, as it traces its origin to caliph Abu Bakr. From their point of view, the esoteric teaching was given to those who had the capacity to contain the direct experiential gnosis of God, which was passed on from teacher to student through the centuries. Worth noting is that the original Islamic scriptures (Qur'an, tafsir Ibn Ishaq ,tafsir al-Tabari) have no mention whatsoever of Sufi traditions or practices. [citation needed]

Some orientalist scholars believe that Sufism was essentially the result of Islam evolving in a more mystic direction. For example, Annemarie Schimmel proposes that Sufism in its early stages of development meant nothing but the interiorization of Islam. According to Louis Massignon: "It is from the Qur’an, constantly recited, meditated, and experienced, that Sufism proceeded, in its origin and its development."

The Sufis dispersed throughout the Middle East, particularly in areas previously under Byzantine influence and control. This period was characterized by the practice of an apprentice (murid) placing himself under the spiritual direction of a Master (shaykh, pir or murshid).

Schools were developed, concerning themselves with topics of mystical experience, education of the heart to purify it of baser instincts, the love of God, and approaching God through progressive stages (maqaam) and states (haal). The schools were championed by reformers who felt their core values and manners were threatened, as the material prosperity of society seemed to them to be eroding the spiritual life.Uwais al-Qarni, Harrm Bin Hian, Hasan Ul-Basri and Sayid Ibn Ul Mussib are regarded as the first mystics among the "Taabi'een" in Islam. Rabia was a female Sufi and known for her love and passion for God. Junayd was among the first theorists of Sufism; he concerned himself with ‘fanaa’ and ‘baqaa’, the state of annihilating the self in the presence of the divine, accompanied by clarity concerning worldly phenomena.

Some muslims believe that Sufism was first formed as a belief in South Asia when Islam mixed with the Hindu, Sikh and Buddhist Cultures, hence why some festivals are shared between the followers of these beliefs.

Al Ghazali's treatises, the "Reconstruction of Religious Sciences" and the "Alchemy of Happiness," argued that Sufism originated from the Qur'an and was thus compatible with mainstream Islamic thought and theology. It should be noted that later on in his life Al Ghazali distanced himself from Sufism and even refuted it. It was around 1000 CE that early Sufi literature, in the form of manuals, treatises, discourses and poetry, became the source of Sufi thinking and meditations.

Sufism, during 1200-1500 CE, experienced an era of increased activity in various parts of the Islamic world. This period is considered as the "Classical Period" or the "Golden Age" of Sufism. Lodges and hospices soon became not only places to house Sufi students, but also places for practicing Sufis and other mystics to stay and retreat.

The propagation of Sufism started in Baghdad in Shiah majority areas, such as Iraq and Khorasan, and spread to Persia, the Indian subcontinent, North Africa, and Muslim Spain. There were tests of conciliation between Sufism and the other Islamic sciences (sharia, fiqh, etc.), as well as the beginning of the Sufi brotherhoods (turuq).

One of the first orders to originate was the Yasawi order, named after Khwajah Ahmed Yesevi in modern Kazakhstan. The Kubrawiya order, originating in Central Asia, was named after Najmeddin Kubra, known as the "saint-producing shaykh" , because a number of his disciples became shaykhs. The most prominent Sufi master of this era is Abdul Qadir Jilani, the founder of the Qadiriyyah order in Iraq. Others included Rumi, founder of the Mevlevi order in Turkey, Sahabuddin Suharwardi in Iran, Moinuddin Chishti and Makhdoom Ashraf in India.

Sufism has some roots in the Shamanic traditions of Middle Asia, and is flexible in terms of religious materiality. These two characteristics of Sufism attracted the nomadic people of middle-western Asia (mainly the current Iranic and Turkic republics of Iran, Afghanistan, Pakistan, Turkmenistan, Uzbekistan, Tajikistan, and Kyrgyzstan). Sufism also spread quickly among the Anatolian Turkmen and among Balkan peoples of modern Albania, Bosnia, Macedonia, and Bulgaria.

The mystics of Khorasan like Ahmad Yasavi and Hajji Bektash Wali were influential in the spread of Sufist Islam.

A number of scholars perceive influences on Sufism from pre-Islamic and non-Islamic schools of mysticism and philosophy. Some of these new perspectives originate from the synthesis of Persian civilization with Islam, an emphasis on spiritual aspects of Islam, and the incorporation of ideas and practices from other mysticisms such as Gnosticism and Judaism into Islam. There are also claims regarding ancient Egyptian roots of Sufism which are not widely accepted. However, most Sunni Muslim scholars consider Sufism to be an integral part of Islam, and do not acknowledge foreign influence on orthodox Sufism.

Sufic development involves the awakening of these spiritual centers of perception that lie dormant in an individual. Each center is associated with a particular color and general area of the body, oftentimes with a particular prophet, and varies from order to order. The help of a guide is considered necessary to help activate these centers. After undergoing this process, the dervish is said to reach a certain type of "completion."

The person gets acquainted with the lataif one by one by Muraqaba (Sufi meditation), Dhikr (Remembrance of God) and purification of one's psyche of negative thoughts, emotions, and actions. Loving God and one's fellow, irrespective of his or her race, religion or nationality, and without consideration for any possible reward, is the key to ascension according to Sufis.

These six "organs" or faculties: Nafs, Qalb, Ruh, Sirr, Khafi & Akhfa, and the purificative activities applied to them, contain the basic orthodox Sufi philosophy. The purification of the elementary passionate nature (Tazkiya-I-Nafs), followed by cleansing of the spiritual heart so that it may acquire a mirror-like purity of reflection (Tazkiya-I-Qalb) and become the receptacle of God's love (Ishq), illumination of the spirit (Tajjali-I-Ruh) fortified by emptying of egoic drives (Taqliyya-I-Sirr) and remembrance of God's attributes (Dhikr), and completion of journey with purification of the last two faculties, Khafi and Akhfa. Through these "organs" or faculties and the transformative results from their activation, the basic Sufi psychology is outlined and bears some resemblance to the schemata of kabbalah and the tantric chakra system.

Although there is no consensus with regard to Sufi cosmology, one can disentangle at least three different cosmographies: Ishraqi visionary universe as expounded by Suhrawardi Maqtul, Neoplatonic view of cosmos cherished by Islamic philosophers like Ibn Sina and Sufis like Ibn Arabi, and Hermetic-Ptolemaic spherical geocentric world. All these doctrines (each one of them claiming to be impeccably orthodox) were freely mixed and juxtaposed, frequently with confusing results – a situation one also encounters in other esoteric doctrines.

One of the most thorough declarations of Sufi cosmology is found in the book God Speaks by Meher Baba.

Dhikr is the remembrance of God commanded in the Qur'an for all Muslims. To engage in dhikr is to have awareness of God according to Islam. Dhikr as a devotional act includes the repetition of divine names, supplications and aphorisms from hadith literature, and sections of the Qur'an. More generally, any activity in which the Muslim maintains awareness of God is considered dhikr.

The practice of Muraqaba and Dhikr have very close resemblance with the practices of the Jewish mystics. Muraqaba is very similar to the Merkavah practice, which is one of the meditations used by Kabbalists to attain higher states of consciousness.

Hadhra is a dance associated with dhikr practiced primarily in the Arab world. The word Hadhra means Presence in Arabic. Sometimes the sufi songs, or dances are performed as an appeal for the Presence of God, his prophets, and angels.

Qawwali is a form of devotional Sufi music common in Pakistan, India, Afganistan, Iran and Turkey. It is known for its secular strains. Some of its modern-day masters have included Nusrat Fateh Ali Khan and the Sabri Brothers. Amir Khusro, a disciple of Nizamuddin Auliya, of the Chishti Order, is credited with inventing Qawwali in the 14th century.